package com.sias.oj.controller;

import cn.hutool.core.io.FileUtil;
import com.sias.oj.common.BaseResponse;
import com.sias.oj.common.ErrorCode;
import com.sias.oj.common.ResultUtils;
import com.sias.oj.constant.FileConstant;
import com.sias.oj.exception.BusinessException;
import com.sias.oj.manager.CosManager;
import com.sias.oj.model.dto.file.UploadFileRequest;
import com.sias.oj.model.entity.User;
import com.sias.oj.model.enums.FileUploadBizEnum;
import com.sias.oj.service.UserService;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.RandomStringUtils;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestPart;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import java.io.File;
import java.util.Arrays;

/**
 * 文件接口
 *
 * @author <a href="https://github.com/sogra">程序员sogra</a>
 */
@RestController
@RequestMapping("/file")
@Slf4j
public class FileController {

  @Resource
  private UserService userService;

  @Resource
  private CosManager cosManager;

  /**
   * 文件上传
   *
   * @param multipartFile
   * @param uploadFileRequest
   * @param request
   * @return
   */
  @PostMapping("/upload")
  public BaseResponse<String> uploadFile(@RequestPart("file") MultipartFile multipartFile,
                                         UploadFileRequest uploadFileRequest, HttpServletRequest request) {
    String biz = uploadFileRequest.getBiz();
    FileUploadBizEnum fileUploadBizEnum = FileUploadBizEnum.getEnumByValue(biz);
    if (fileUploadBizEnum == null) {
      throw new BusinessException(ErrorCode.PARAMS_ERROR);
    }
    validFile(multipartFile, fileUploadBizEnum);
    User loginUser = userService.getLoginUser(request);
    // 文件目录：根据业务、用户来划分
    String uuid = RandomStringUtils.randomAlphanumeric(8);
    String filename = uuid + "-" + multipartFile.getOriginalFilename();
    String filepath = String.format("/%s/%s/%s", fileUploadBizEnum.getValue(), loginUser.getId(), filename);
    File file = null;
    try {
      // 上传文件
      file = File.createTempFile(filepath, null);
      multipartFile.transferTo(file);
      cosManager.putObject(filepath, file);
      // 返回可访问地址
      return ResultUtils.success(FileConstant.COS_HOST + filepath);
    } catch (Exception e) {
      log.error("file upload error, filepath = " + filepath, e);
      throw new BusinessException(ErrorCode.SYSTEM_ERROR, "上传失败");
    } finally {
      if (file != null) {
        // 删除临时文件
        boolean delete = file.delete();
        if (!delete) {
          log.error("file delete error, filepath = {}", filepath);
        }
      }
    }
  }

  /**
   * 校验文件
   *
   * @param multipartFile
   * @param fileUploadBizEnum 业务类型
   */
  private void validFile(MultipartFile multipartFile, FileUploadBizEnum fileUploadBizEnum) {
    // 文件大小
    long fileSize = multipartFile.getSize();
    // 文件后缀
    String fileSuffix = FileUtil.getSuffix(multipartFile.getOriginalFilename());
    final long ONE_M = 1024 * 1024L;
    if (FileUploadBizEnum.USER_AVATAR.equals(fileUploadBizEnum)) {
      if (fileSize > ONE_M) {
        throw new BusinessException(ErrorCode.PARAMS_ERROR, "文件大小不能超过 1M");
      }
      if (!Arrays.asList("jpeg", "jpg", "svg", "png", "webp").contains(fileSuffix)) {
        throw new BusinessException(ErrorCode.PARAMS_ERROR, "文件类型错误");
      }
    }
  }
}
